1. Field of the Invention
Embodiments of the invention relate to the field of circuits, and more specifically, to mismatch-shaping circuits.
2. Description of Related Art
A digital-to-analog converter (DAC) is usually implemented by an array of unit elements. Each unit element contributes to the output analog signal when selected. If all unit elements are identical to provide an exact amount of contribution (e.g., same weights) when selected, the DAC may be perfectly linear. In reality, circuit elements can never be made identical. Any mismatch may result in both noises and non-linearity.
Existing techniques to implement mismatch-shaping circuits have a number of drawbacks. One technique uses a quantizer and a limiter in the generator for generating 2nd order sequences. Another technique uses a 3-state accumulator and an M-state accumulator. These techniques are typically expensive, requiring hardware components such as a quantizer, a limiter, or an accumulator.